- The first Zika-related death in U.S. territory occurred in February
- A 70-year-old man died of bleeding complications after recovering from Zika
The elderly man, who lived in the San Juan metro area, contracted Zika and was treated for symptoms that lasted less than a week, said Tyler Sharp, an epidemiologist at the Centers for Disease Control and Prevention Dengue Branch in San Juan, Puerto Rico.
"A few days after his recovery, he returned to the hospital with signs of a bleeding disorder and was diagnosed with immune thrombocytopenic purpura, or ITP," Sharp said. "That's a disorder where a person's immune system attacks the blood cells, called platelets, that allow clotting.
"As an elderly man, this individual did have some underlying health conditions, but they were not life-threatening and not likely to have led to his death."
This is the ninth known case of bleeding associated with the Zika virus. "There have been four cases in French Polynesia, one case from Suriname and three cases in Colombia that were all diagnosed with ITP," Sharp said. The individuals in French Polynesia and Suriname survived; those in Colombia did not.
"We do not know if there are risk factors in the person infected with Zika that would make them more suspectible to developing ITP," Sharp said. "Bleeding typically begins in the mouth and from the gums, and progresses with easy bruising and petechiae, or tiny, round pinpoints that appear on the skin as a result of bleeding."
Sharp added that the relationship between bleeding and Zika might be similar to that which occurs between Zika and Guillain-Barre Syndrome
, a rare disorder in which the body's immune system attacks the nerves.
"To the best of our understanding, the ITP happens after the Zika illness resolves," he said. "Then the antibodies begin to cross-react with other cells in the body. In Guillain-Barre, they attack nerves. In ITP, the antibodies attack platelets."
The CDC said they have tested over 6,000 specimens since Puerto Rico became the first U.S. jurisdiction to report local transmission of the Zika virus; 683 showed evidence of current or recent infection. Nine of those cases, or 1 percent, also showed signs of low blood platelets.